Poster Presentation Clinical Oncology Society of Australia Annual Scientific Meeting 2026

Increased Risk of Clinically Significant Prostate Cancer Among Melanoma Survivors: A Population-Based Cohort Study (146461)

Visalini Nair-Shalliker 1 , Albert Bang 1 , Sam Egger 1 , Karen Chiam 1 , Manish Patel 2 , Bosco Wu 3 , Michael David 1 , David Smith 1
  1. The Daffodil Centre, The University of Sydney, a joint venture with Cancer Council New South Wales, Sydney, New South Wales, Australia
  2. The University of Sydney, Sydney, NSW
  3. Department of Clinical Medicine, Macquarie University, Sydney, Australia

Background: Prostate cancer (PC) risk is increased in melanoma survivors. This study aims to evaluate the incidence of clinically significant PC among melanoma survivors.

Methods: Male participants in the Sax Institute’s 45 and Up Study in New South Wales Australia, were recruited between 2005-2009. Self-reported data were linked to NSW Cancer Registry and Services Australia by the Centre for Health Record Linkage to identify melanomas diagnosed between 1/1/1994 and 12 months before study recruitment and incident PC defined as low-risk (Gleason <7; Grade group (GG) 1), intermediate-risk (Gleason=7; GG2-GG3) and high-risk (Gleason>7; GG4-GG5). Multivariable Joint Cox regression analyses estimated hazard ratios (HRs), adjusting for socio-demographic and pre-diagnostic PSA testing frequency.

Key findings and limitations: Of 98,980 eligible men, 1899 were diagnosed with melanoma during the melanoma ascertainment period (in situ=500; invasive=1389) and 6626 incident PC (low-risk=1689; intermediate-risk=2333; high-risk (including advanced spread) =2604) diagnosed during follow-up until 31st December 2019. Men with a history of melanoma diagnosis (vs. no melanoma) had increased risk of intermediate-risk PC (HRadjusted=1.53;95%CI:1.20-1.95), which was higher for men diagnosed with ≥2 melanomas (HRadjusted=2.96;95% CI:1.11-7.91), invasive melanoma (HRadjusted=1.67;95%CI:1.27-2.20), and truncal melanoma (HRadjusted=1.70;95%CI:1.20-2.41). As an observational study, the findings are subject to potential residual confounding despite adjustment for known factors.

Conclusion and clinical implications: Melanoma survivors have an increased risk of intermediate-risk PC, with the strongest associations observed among men with multiple, invasive, or truncal melanomas. These findings suggest a potential shared aetiology and highlight the importance of tailored PC awareness and risk stratification in melanoma survivors.